I have a downflow furnace in my attic... before the furnace kicks on, there is a loud sound similar to that of a washing machine draining water... is there something wrong or is that normal? Also, the condensation line makes a lot of suction noise... is there any way to quiet that? Thanks

The condensate line is just a drain line. If it is making noise I would insulate it to help reduce the noise. The next time you have the service company out I would suggest you mention the noise to them.